Ticket validation in transit systems enables a transit system to track passengers and payments within the transit system. Such functionality lies at the heart of transit systems. Some transit systems use “pass through” validators with entry slots into which tickets (typically a physical medium with a paper or plastic substrate onto which ticket information is encoded visually, magnetically, and/or otherwise written) are inserted, and a separate exit slot out of which tickets are then collected by the passenger. The tickets travel inside the validators from the entry slot to the exit slot, during which information is extracted from the ticket and the ticket is validated. Depending on the type of entry gate in which the validator is used, a physical barricade or other entry-limiting mechanism may be moved (automatically or manually by the passenger) once the ticket is validated. Among other advantages, these validators can quickly validate tickets to help preserve and promote a paced throughput (e.g., 33 passengers per minute or other rate) through entry gates and/or exit gates.
These validators, however, have limitations. Because tickets enter into the validators through external openings, the validators are susceptible to water, dirt, and other debris that enters the slot. Thus, pass-through validators have rarely been used outdoors, where there is an increased likelihood that water and/or other debris will enter the validator. Improvements in preventing debris ingression in such validation systems is desired.